#include <LiquidCrystal_I2C.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);

void setup() {
  lcd.init();
  lcd.backlight();
  zobraz("ahoj");
}

#define BETA 3950
float lastCelsius = 0;
float celsius = 0;

void loop() {

  int reading = analogRead(A0);
  lastCelsius = celsius;
  celsius = 1 / (log(1 / (1023.0 / reading - 1)) / BETA + 1.0 / 298.15) - 273.15;

  if(lastCelsius!=celsius){
    zobraz(String(celsius,1));
  }
}

void zobraz(String vypis){
    lcd.clear();
    lcd.setCursor(16-vypis.length(),1);
    lcd.print(vypis);
  }